Rotary cutter for a dredge cutting head



|. B. HUMPHREYS 2,926,436

ROTARY CUTTER FOR A DREDGE CUTTING HEAD March 1, 1960 Filed Jan. 27,1955 5 Sheets-Sheet 1 INVENTOR. [TA B. HUMP/ways Y T ATTORNEY March 1,1960 l. B. HUMFHREYS 2,926,436

ROTARY CUTTER FOR A DREDGE CUTTING HEAD Filed Jan. 27, 1955 5Sheets-Sheet 2 III- . Fl G. 5 INVENTOR.

IRA B. HUMPHREYS BY 8 T TORNE Y March 1, 1960 l. B. HUMPHREYS ROTARYCUTTER FOR A DREDGE CUTTING HEAD 5 Sheets-Sheet 3 Filed Jan, 27, 1955 HTT'ORNE Y March 1, 1960 l. B. HUMPHREYS ROTARY CUTTER FOR A DREDGECUTTING HEAD 5 Sheets-Sheet 4 Filed Jan. 27, 1955 INVENTOR. IRA B.HUMPHREYS ATTO March 1, 1960 B. HUMPHREYS 2,926,436

ROTARY CUTTER FOR A DREDGE CUTTING HEAD Filed Jan. 27, 1955 5Sheets-Sheet 5 5O Io 21 22 '25 ,P 20 \i 29 19 --23 FIG. 6 2a I INVENTOR.II PA B HUMPHIPEYS I 2,95,42 6 noTAR'Ypu'r'rER mitt DREDGE CUTTING HEADv V Ira B. Humphreys, Denver, 010., assignor toHumphreys EngineeringCo'mpa'ny,.Deuve'r, C010,; a corporation of Colorado Appraise many 27,os s, *l \T o."484, 401

' 7 Claims. cum-51 The-present invention relates to 'a rotary cutter andmore particularly and specifically it is concerned with the 'provisionofa new and improved reversible, rotating cutter'head of a type to beused in dredging operations. t Certain prior-art-constructioris ofdredge cutting heads have embodied-the provision of rotatinghea'dsprovided withspli'ned or spiral type blades thereon, which bladesare designed to present "a fixed cutting angle in the direction "ofrotation of the head. r

In dredging with cutter heads of prior constructions the headshave'us'ually been supported. onthe extended end of a ladder. which hasits second end hinged to the front 'or forward end of a dredge bargeor'scowso that the ladder and head can be moved Vertically inI order toregulate the depth of cut. j The front end of the barge along with theladder and head have normally been: moved from side to side to swing thehead in a cutting. arc by use of spuds serving to alternately pivot therearward end of the barge. These spudsalsjc3 serve to permifirelo'cationand anchoring of the barge progressively-relative to'the material to be"cut.

Most 'pribr cut'ting'head constructions arefdesign'ed to out whilerotatingiin one direction of head swing in order to dislodge materialtobe taken up by suction apparatus. During the opposite or back swing ofthe cutter head the cutting edges of the blades are oppositely disposedto the direction of swing and-the rotation of the blades has beendownward into the bank of material to be cut ratherthan upward as isdesired-forqeificient operation. Thus, the 'e'fficiency of the cuttinghead is greatly reduced during the return swing of thehead andladder:during a substantial portion of the over-all dredgingoperation. naddition, the action of the cutting head on the material to be dislodgedin the returnswingof Xthe'fhe'ad and ladder is such'that the dislodgedmat'en'al is normally moved away frornthe dredge suctioni 'ftherebyleaving a substantialamodn'tof material which-mus'tibe taken up by 'aseparate cleanup operation... Stilifurther, the downward movement or thecutting blades on the return swing of the ladder and head producesa-tendency in the blades to cause the cutter head to 'climbor .walkon.the material to be dislodged rather than efficiently dislodge it asis desired. p.

Accordingly, the use of prior constructions which in: clude cuttingblades having a-fixed positionhasgreatly hampered the efiiciencyandsubstantiallyincreased the cost. of dredging operatio 7 Therefore, itis a general object of swing of the scow;

Another object of the present invention lies inthe prq I vision of arotating cutting h ead in which th e gutting blades are supported insuch a manner as to befreely movable between two fixediopposite cuttingpos1 ons,

and a head construction wher n the proper positioning the present inven-I terconnecting said blades to produce zszatss Patented Mani- 1 960 theprovision of a reversible, rotating cutting head which is readilyadaptable for installation in both new 'aswell as existing dredgeequipment to be supported in 'a' simple andconventional manner on theusual boom or 'la'ddenof thedredgezmechanism. Furthen'the cuttingheadconstituting the *present invention is of a construction whichlendsreadilyto efficient operation conjunctively with the suctionapparatus of underwater dredging equipment.

Yet another object of the present invention is to provide a cutting headconstruction which the cutting blades. are movable between two fixedcutting positions and :whereinthe proper positioning ofjjthe bladesrelative to the "directionof out is automatically obtained by theresistance of the material to 'be cut. This 'a'ut'oi'nat'ic positioninginitiated by the resistance of the material to "be cutoper'ating againstone or more of the eutting blades .will, byreason of the novel andutilitarian con struction of the present cutter head, automatically andsubstantially simultaneously move 'allof the cutfer'bl'ades to identicaland proper cutting positions.

.A still further object is the provision of a rotating cutteriheadparticularly. adaptable to dredging operations which-is extremelyeflicient and durable in use requiring a minimum of maintenance andupkeep overextended Periods of time.

in the light or the accompanying drawings.

Thenature of'the present invention maybe stated'in genera'kter'ms asi'ricluding'a cutting .h'eadisupp'orted on and operate'd'by'a reversibledrive shaft: including -a hub membenrigidly affiried to the drive shaft,a-plurality of cutting blades pivotally supported by said hub, saidblades being spaced about said hub, stop means associated with each ofsaid blades for limiting pivotal move ment thereof in two directions,and indexing means insubstantially simult'aneous pivotal movement.

Turning now to the accompanying drawings, in which like numeralsdesignate similar parts throughout the severalviews; V a

Fig. :1 is aperspective viewofthe fcutter head as associatedwithfragmentary portions,of 'a dredgefappara'tus ladder.

, Fig. 3.

Fig. 8 is a plan View of the cutter head associatedwith the dredgeapparatus, and r rtion to provide af;dredge:cuttingheadlwhich embodies21 unique and-advantageous blade construction .whichper-r mits theheadto cut'equally well in either direction pf F head and ladder relativetlo the} dredge ,or;

.Fig. 2 is; abottomplan view of association with said ladder.

Eig.'3lis' a top plan view of said cutter head drive shaftshown insection. V

- Fig. 4 is a fragmentary bottom plan illustrating the cutter bladesinone cutting positio the. cutter head in Fig. 5 is a view similar to Fig.4 with-the cutter blades in the opposite cutting position.

Fig. v6 is a fragmentary section taken on line 6-6 of Fig-7 "is afragmentary bottoin plan of a modified embodiment of the cutter headiFin. 9 is a fragmentary side elevation of Fig. 8..

cutting head constituting the'present invention and the numeralll-generally designates the ladder or boom arrangement fromwhich thecutter head is operativel'ysup With articnlarreference to;Figs. 10 and11 of,;the drawings there is shown, for purposes of illustration only;

a dredge barges: scow apparatus With which the Gutter with at 1 headconstituting the present invention is cooperatively associated.

In these Figs. and 11 the cutter head 10 is carried at one end of aladder or boom 13, the second end of which is hinged transversely on theforward end of' the barge to permit vertical movement of its extendedend. The forward end of the barge is provided with a vertical mast 14and a forwardly angularly extending mast or-sprite 15 which extendsoutwardly over the hinged ladder 13.

A set of cables 16 are secured to the extended end 0 the ladder adjacentthe cutter head and connect through a series of blocks 17 and sheave 18on the sprite 15 and the mast 14 respectively with a power winch19.0n'the barge. This arrangement provides for controlled verticalpositioning of the ladder and cutter head.

The rearward end of the barge 12 is alternately pivotally fixed by apair of spaced spuds- 20. A second winch 21 receives cables 22 and 23which extend through sheaves 24 on the boom or sprite 15 to deadmenlocated on opposed sides of the barge.

Lateral, swinging movement of the head is obtained by swinging theforward end of the barge alternately about one spud and then the otherthrough winch control of cables 22 and 23.

Associated with the boom or ladder 13 is a drive shaft 25 mounted bysuitable spaced bearings 26 along the length of the ladder, and thedrive shaft is rotatably driven by means of a reversible motor 27 whichis. also electrically controlled from a convenient point on board thescow ordredge.

In addition to the shaft 25 a suction line 28 is sup ported the lengthof the boom 13 with its suction end located adjacent the extended endof'the boom and its opposite or discharge end flexibly coupled through asuitable pump 29 to a discharge line 30 which may be arranged todischarge the dredged material at any desirable point either on the scowor some point remote thereto.

The extended end of the drive shaft 25 is provided with a concentricguard plate 31 which is supported from the boom or ladder 13 to form acircular guard for the end of the ladder concentrically about theshaft." Additionally, as may be seen in Fig. 1, the guard plate 31together with the boom 13 forms a base to which the vertical movementcontrol cables 16 are swivelly mounted as at 32.

Referring now to Fig. 6 itis seen that the extended end of the shaft 25is provided with a rigidly secured hub 33 which hub is substantiallycylindrical in cross 'sec tion. The lower end portion of the hub forms abaseto which a plurality of tubular posts 34 are secured in' equallyspaced relationship thereabout, thepost34 extending upwardly from thehub at an angle diverging from the axial center line of the shaft 25.The upper extended ends of the post 34 are rigidly secured to a top ringsupport member 35 which ring is concentrically positioned relative tothe shaft 25.

Associated with each of the tubular posts 34 is an arcuate cutting blade36 which has a fiat turned-over lip portion 37 beneath the foot of thepost member 34 and a second turned-over lip portion 38 overlying theupper face of the'top of the post 34. A rigid shaft 39 extends througheach of the tubular posts 34 to rigidly engage the lip portions 37 ofeach of the arcuate blades below the posts 34 and the turned-overlipportions 38. of the baldes above the top of the posts. In accordancewith the foregoing construction the arcuate cutting blades 36 are thusrigidly secured at each end of the extended ends of the shafts 39 to besupported for pivotal movement about the axis of the shafts 39 and thetubular posts 34 which act as bearing housings'for the shafts.

As is best illustrated in Figs. 2 through 5, the top ring member 35 isprovided with a plurality of buttress type stop members 40 which arelocated about the outer circumferential edge of the top'ring inoppositely disposed pairs, each pair being associated with one of saidblades and defining the extreme limits within which said blades arecapable of pivotal movement. The stop members 40 are of such a size andconfiguration so as to engage the opposed edge portions of the cuttingblades 36 adjacent the top ring member 35.

Associated. with the cutting blades 36 are a plurality of indexingchains 41, said chains all being of equal length and each chaininterconnecting adjacent cutting blades about the cutting head. Theindexing chains 41' are secured at each end to mounting brackets 42which are rigidly secured to the inner faces of the cutting blades 36atidentical positions thereon throughout all cated by the arrow 44 would,when one of the blades the blades of the head.

The normal tension of the indexing chains 41 is such as to causesubstantial simultaneous movement in the same direction of all thecutting blades of the head when one of said blades is moved rotatably inone direction concentrically about its supporting tube.

It is understood that the positioning of the stop members 40 about thetop ring 35 is a predetermined calculation so as to permit the cuttingblades to present a leading cutting edge to the material to be cut in aposition to afford the utmost efficiency in the cutting action of theblades. With reference to Fig. 4, it is seen that for rotation of thecutting head in the direction indicated by the arow 43 the cuttingblades, by reason of the resistance offered by the material to be cut,will be simultaneously moved through the medium of the indexing chains41 to bring the trailing edges of the blades to bear against what wouldthen be the rear stop members 40 so that the forward or leading edge ofthe cutting blades in the direction of rotation of the head will be suchas to produce the maximum cutting efiiciency.

With reference to Fig. 5, it can be seen that the reversed rotation ofthe cutting head in the direction indiwas moved by the'resistance of thecutting material, cause the blades to move to positions opposite tothose illustrated in Fig. 4 to present the leading cutting edge in aposition substantially identical with those cutting edges provided bythe positioning of the cutting blades as illustrated in Fig. 4.

In Fig. 7 of the drawings there is illustrated a modified constructionof the cutter head wherein the head is substantially identical in allrespects to the preferred embodiment heretofore described with theexception of the inv, dexing chains 41 which, in the present embodimentare replaced by coil springs 46. The coil springs 46 are.of aprecalculated length and tensionand are connected by U bolts 47 at eachend thereof to the mountingbrackets 42 on the inner face of each of thecutting blades 36. I

- The springs 46 in this modified construction are under a predeterminedtension which acts in a plane at right angles to the drive shaft 25 ofthe cutting head thereby setting up a precalculated, hexagonal diagramof forces about the cutting head. These forces established by thesprings 46 are such that the springs will hold the blades against thestops 40 in one direction around the head until such time as rotation ofthe cutting head is reversed whereupon the-force produced by theopposition of the material engaged by the cutting blade is placed inopposition to the force of the'spring whereupon each cutting blade willpivot into abutment with the opposite stop as each blade engages thematerial to be cut. In

this manner each blade is brought to a location where' it presents theproper and most efficient cutting edge position relative to the materialto be cut and in which location it is held by the force of the springsuntil direction of rotation of the head is again reversed.

In accordance with the construction of the cutting head described in theforegoing it can now be readily seen that a dredge cutting head has beenprovided which 1 will cut in all lateral and vertical directions ofmovement of the head with maximum efliciency in any direction by virtueof the automatic positioning of the movable cutting blades. It is alsoevident that for under water dredging operations the construction of thepresent cutting head Will provide an efiicient cutting operation topermit the materials to be cut, together with the surrounding water tobe drawn upwardly into the suction line 28 through a suction nozzle oropening 45 (Fig. 2) which opens through the support plate 31 adjacentthe top ring 35 of the cutter head. 4

It is additionally evident that a construction has been provided whichsatisfies all of the objects and advantages heretofore attributed to thepresent invention and which is capable of numerous modifications andarrangements without departing from the scope of the present inventionas it is defined and limited bythe hereinafter appended claims.

What is claimed is as follows:

1. In a hydraulic dredging apparatus, a cutting head and means forsupporting and selectively rotating the head in either direction, saidhead comprising: a plurality of elongated spaced apart blades, meanssupporting said blades on the head for oscillation about itslongitudinal axis within fixed limits, each blade having acutting edgeat each of its longitudinal side edges, a plurality of indexing means,an indexing means being positioned between each adjacent pair of blades,each indexing means constituting a tie between and supported by a pairof adjacent blades by having one of its ends secured to one blade andits other end secured to the other blade, and the indexing meansinterconnecting the blades serially for producing substantiallysimultaneous oscillation of all the blades upon oscillation of oneblade.

2. A construction as defined in claim 1 wherein, the indexing meanscomprises a plurality of coil springs of predetermined tension with eachspring interconnecting two adjacent blades. 7

3. A construction as defined in claim 1 wherein, the indexing meanscomprises a plurality of chains with each chain interconnecting twoadjacent blades. 7 V

4. In a hydraulic dredging apparatus, a cutting'head and means forsupporting and selectively rotating the head in either direction, saidhead comprising: a plurality of elongated spaced apart blades each beingsupported on the head for oscillation about its longitudinal axis, eachblade having a cutting edge at each of its longitudinal side edges, aplurality of pairs of stop members carried by the head, the members ofeach pair of stop members being positioned one on each side of each ofthe blades at the cutting edge sides thereof for limiting the pivotaloscillatory movement of each of the blades in each direction.

5. In a hydraulic dredging apparatus, a cutting head and means forsupporting and selectively rotating the head in either direction, saidhead comprising: a plurality of elongated spaced apart blades each beingsupported on the head for oscillation about its longitudinal axis, eachblade having a cutting edge at each of its longitudinal side edges, aplurality of pairs of stop members carried by the head, the members ofeach pair of stop members being positioned one on each side of each ofthe blades at the cutting edge sides thereof for limiting the pivotaloscillatory movement of each of the blades inqeach direction, aplurality of indexing means, an indexing means being positioned betweeneach adjacent pair of blades, each indexing means constituting a tiebetween and supported by a pair of adjacent bladesby having one of itsends secured to one blade and its other end secured to the other blade,and the indexing means interconnecting the blades serially for producingsubstantially simultaneous oscillation of all the blades uponoscillation of one blade. 7

6. A construction as defined in claim 5 wherein, the

indexing means comprises a plurality of coil springs of predeterminedtension with each spring interconnecting two adjacent blades.

7. A construction as defined in claim 5 wherein, the indexing meanscomprises a plurality of chains with each chain interconnecting twoadjacent blades.

References Cited in the file of this patent UNITED STATES PATENTS

